Question

If m+n=5 and mn=6 than find the value of m(cuib)+n(cuib) m (squre) + n (sque)

Answer 1

m+n=5

squaring both the side

m²+n²+2mn=25

m²+n²=13

No m³+n³=(n+m)(m²+n²+mn)

=5(13—6)

=35

Hence m²+n²(m³+n³—13(35)=445

Answer 2

CORRECT QUESTION:

If m + n = 5 and mn = 6 then, find the value of (m³ + n³) (m² + n²).

ANSWER:

• (m³ + n³) (m² + n²) = 455

GIVEN:

• Value of m + n = 5 and mn = 6.

TO FIND:

• The value of (m³ + n³) (m² + n²)

EXPLANATION:

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m² + n² = (m + n)² - 2mn

Substitute m + n = 5, mn = 6.

m² + n² = (5)² - 2(6)

m² + n² = 25 - 12

m² + n² = 13

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m³ + n³ = (m + n)(m² + n² - mn)

Substitute m + n = 5, mn = 6, m² + n² = 13

m³ + n³ = (5)(13 - 6)

m³ + n³ = (5)(7)

m³ + n³ = 35

(m³ + n³) (m² + n²) = 35 × 13

(m³ + n³) (m² + n²) = 455

Hence the value of (m³ + n³) (m² + n²) = 455